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### Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 7:07 pm
What does it mean for something to be additive?

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 7:09 pm
It's saying that since enthalpy is a state property (not dependent on the path taken to obtain that state), enthalpies can be added (and subtracted).
For example, Hproducts - Hreactants = Change in H

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 7:54 pm
One of the examples that Dr. Lavelle gave for another state property is altitude. For altitude, the path doesn't matter. What matters is where the hiker ends up.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 8:02 pm
it basically means the delta H values can be added together (even if it's a negative number, which will just make the addition into a subtraction)

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 8:21 pm
Because Enthalpy is a state function, only the state matters. In other words, what matters is the state, not the way that those states were obtained or the path that led them there. This is what allows enthalpy to be additive.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 8:40 pm
This is because Enthalpy is a state property. Only the initial and final values are relevant, the path taken to get to the final value does not matter.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 9:02 pm
Enthalpy is additive because it is a state function, meaning it can be added or subtracted.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 9:05 pm
being additive means that different enthalpies of different reactions can be added. this is true because enthalpy is a state function.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 9:28 pm
Because enthalpies of different reactions can be added together, it is said to be additive.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 9:41 pm
It just means that, since enthalpy is a state property, different enthalpies can be added together.

### Re: Enthalpy is said to be additive

Posted: Sun Jan 26, 2020 9:53 pm
enthalpies of different reactions can be added together to get the total enthalpy of the system in its change from reactants to products